I have the same thing, my friend...chest pressure, tightness, even pain and shortness of breath. It's caused by stress, anxiety, depression (not the clinical, just the occasional depression...you know, sadness.)
The only cure that I have found, short of medication for anxiety which I won't take under any circumstances (but came close to considering last year about this time), is just doing things to take your mind off it. For me, it was focusing on that Beetle...that did me a world of good.
Probably all my little obsessions are my way of dealing with the stresses in my life...they don't run us to ruin, so I don't worry about them and I gotta think that it's better than medication. Once I feel better, the obsession wanes, although the commitment I've made during it doesn't.
Find something that makes you basically happy.
If any shrink ever tried to tell me that my obsessions are unhealthy, I'd tell 'em that coping with stress in a productive way is better than taking a pill and to blow it out...well, you know.
This is not medical advise and you should REALLY make sure you always are current on your health evaluations...IOW, get a check-up!
I'm not a doctor, although I play one in my mind.
You and I seem to be pretty intense people and I think this is just how it manifests it's self.
Since this latest round kicked in around the time I got the cholesterol numbers, I'm thinking that's probably what it is. It has been in the past.
If I didh't have all the risk factors, I'd write it off as mini panic attack.